Hot-air furnace.



R. L. POLLOCK.

HOT AIR FURNACE.

APPLICATION FILED MAR. 31. I9I.

Lm Patented Sem. 25,1917.

3 SHEETS-SHEET I.

| I I I 3 SHEETS-SHEET 2.

Patented Sept. 25, 1917.

R. L. POLLOCK.

HOT AIR FURNACE.

APPLICATION FILED IIIAII. 31. I9II.

WIT/VESSES R. L. POLLOCK.

HOT AIR FURNACE.

APPLICATION FILED MAR. 31, IsIz.

3 SHEETS-SHEET 3.

WIT/VESSES y INI/EIVTUR ye/M WQ A24/00M@ i i fila" ROBERT LINCOLN POLLOCK, 0F STERLING, KANSAS.

HOT-AIR FURNACE.

lowing is a full, clear, and exact description.

My invention relates to hot-air heating furnaces and has for its prime object to utilizeto the fullest extent the maximum interior surface of the furnace for heating the air. The stated object is attained by constructing the furnace with inner and Outer walls, thereby forming an air space within the furnace at all sides thereof, and providing means affording passages through which the air is caused t0 pass and subjected to the heat of the re box, the passages including air pipes associated with the grate, air pipes in the fire box near thetop, and air boxes transverse to the upper air pipes above the same, the arrangement being such as to cause the air to pass through the furnace directly at the grate and above the same to be effectively subjected to the heat thereof. The structure includes also an indirect smoke passage arranged so that the heat of the smoke may be availed of for heating the air in the furnace; as well as vertical air shafts rising in the furnace from the air pit to the top. .l Other objects of the invention and the advantages of the novel features characterizing theillustrated practical embodiment of the invention will appear as the description proceeds. v y

Reference is to be had to the accompanying drawings forming a part'of this specification in which similar reference characters indicate corresponding parts in all the views.

Figure lis a longitudinal vertical section on the line 1%1, Fig. 4;

Fig. 2 is a front view of the furnace;

Fig. 3 is a transverse section on the line 3-3, Fig. 1;

Fig. y4 is a horizontal section on theline 1 -4, Fig. 1;

Fig. 5 is a longitudinal vertical section on the line 5 5, Fig. 4;

Fig. 6 is a horizontal section on the line Fig. 7 i's a horizontal section on the line 7,-7, Fig. 1.

Speccation of Letters Patent.

Patented Sept. 25, 1917.

Appneation med March a1, 1917. serial No. 158,834.

My improved furnace is constructed Vwith an outer wall 10 and an inner'structure or furnace proper 11 between the walls of which and outer wall 10, an air space is produced at all vsides of the furnace. Back walls 12, 13 are provided in the furnace at the back of the ash pit 14 and fire box 16,

,the wall `12 terminating at about the level `of the grate and being 'oined at its top With the rear wall 13 and orming an air space between said walls 12 and 13. `The numeral l5 indicates the ash box door and 17, the

lire door, the openings closed by the respec` tive doors leading to the ash box and fire box through tubular structure 18, 19, as best seen in Fig. 1. Anyl approved means may be provided for supplying air to the interior of the furnace to be heated, a cold air pit being indicated in Figs. 2 and 3 by dotted lines and designated by the numeral 20. rl`he top 21 of the furnace proper or inner structure is spaced from the top 22 of the outer wall structure 10 and the said top 22 is provided with any suitable number of air outlets 23 which in practice will deliver the heated air to any approved system of distributing pipes (not shown). On the inner top 21 a water pan 24 is provided to which an inlet.

pipe 25 leads, said pipe havingya funnel 26.

Leading from the fire box 16 is a smoke outlet 27 which communicates with a U- shaped smoke passage 28 extending to the vbottom of the furnace, then upwardly and communicating by a smoke outlet 29 with thel Hue or chimney 30. In the top of the smoke passage 27 is an opening 31 leading to the direct smoke passage 32 which communicates also with the chimney 30, the said hole 31 being controlled by a damper 33, the rod 34 of which extendsto the outside'of the furnace and is provided with a suitable handle 35. The arrangement is such that with ythe damper33 raised, the smoke will tend to pass directly through the passage 32 to the chimney, whereas with the said damper closed the smoke will pass indirectly to the chimneyvthrough the smoke passage 28.

In order to utilize the heat from the smoke passing through the passage 28, said passage is made to form an air chamber 36, the upper end of which opens into the space between the tops 21, 22. It will be observed from Figs. 4 and 7 that the passage 28 and chamber 36 extend the full width of the inner structure 11, so that a large heating surface is thus produced to heat the air in the chamber 36. 0n the walls of smoke passage 28 radiating knobs 28a may be employed.

. At each side of the air chamber 36 in the space between the inner and outer side walls of the furnace, are vertical air shafts 37, the lower ends of said air shafts having air inlets 38, the inner sides of said air shafts being open to chamber 36, and the upper ends of said air passages being open to the air space at the top of the furnace. The numeral 39, Figs. 1 and 5, indicates transverse clean-out o enings yextending through the air shafts 3 at the lower ends thereo to the bend of the smoke passage 28, said clean-out openings being accessible through doors I1ndicated at 39a, formed in the side walls 10, 11 as indicated in Figs. 1, 5, 6 and 7.v In addition to the vertical air shafts 37, air passes`r upwardly from the air pit 20 to the chamber or space 40 in the rear of the wall 13, said space extending at the top thereof at both sides of the smoke passage 27.

In order to effectively utilize the heat of the fire box, I provide air pipes '4l associated with and forming part of the grate, the said pipes alternating with grate bars 42 adapted to be operated as hereinafter described. The inner ends 43 of the pipes I41 extend into the air space between the walls .12 and 13 and advantageously are downturned, while the front ends 44 are upturned in the space between the inner and outer front walls. fire box additional transverse air` pipesl 45 extend, the inner ends 46 being downturned in the air space 40 in the rear of the wall 13, while the forward ends 47 are upturned and positioned in the space between the inner and outer front walls. It will thus be seen that the air pipes 41 are subjected tothe heat at the grate while the upper pipes 48 are subjected to the heat in the upper portion of the fire box and air will thus be caused to rise in the ends 44, 47, the air being drawn in through the rear ends of the pipes.

Above the pipes 45 and at right angles thereto I provide in the top of the fire box transverse air boxes 48 and as will be understood from Figs. 3 and 4, the said boxes48 have air inlets 49 at one end at the under side and air outlets 50'l at the opposite'ends at the top. The inlets and outlets of alternate air boxes 48 are reversed so that air passes oppositely in alternate boxes from one side of the furnace to the other, thereby causing air to pass from each side to the opposite side in certain of the boxes, while the position of the said air boxes in the top of the fire box will cause an effective circulation of the air in an obvious manner.

In order to rock the grate bars 42 they are formed rigid with a trans verse centrally dis- In the upper portion of thel posed rocker bar 51 which is seated in bear-y l ings 52 in the opposite sides of the lire box.

`head or handle 55.

It will be readily understood that the heat of the fire box is effectively utilized by highly heating the air and much of the heat may be taken from the smoke by causing it to pass through the passage 28.

I wish to state in conclusion that although the illustrated example constitutes a practical embodiment of my invention, I do not limit myself strictly to the mechanical'details herein illustrated, since manifestly the same can be considerably varied without departure from the spirit of the invention as defined in the appended claims. A

I-Iaving thus described my invention, I claim as new, and desire to secure by Letters Patent: y v

1. A hot-air furnace having inner and outer walls forming an air space therebetween, vthere being a communicating air space at the to of the furnace, a fire box, a

smoke flue, a -shaped smoke passage communicating with the re box and with the shaped smoke passage extending at the front and back of and beneath ythe said vertical chamber, the said vertical air chamber and U-shaped smoke passage extending approximately from one inner side wall to the other, and vertical air shafts between the inner and outer side walls adjacent to the ends of the said vertical air chamber, said air shafts having air inlets at their lower y ends and communicating at the sides with the said vertical airj chamber and at the upper ends with the air space at the top of the furnace. i

2. A hot-air furnace comprising inner and outer walls forming an air space around the furnace at all sides, a fire box in the furnace near the front within the inner walls, a

smokefiue at the back of the furnace, a U- shaped smoke passage communicating with the fire box and with said smoke flue, a verltical air chamber at the front and back of and beneath which the said smoke passage extends, vertical air shafts between the inner andouter walls atthe sides of the said vertical air chamber and communicating therewith, and a vertical air chamber between the back of the fire box and the front portion ofthe said U-shapedsmoke passage.

3. A hot-air furnace having an outer wall, an inner structure within the outer wall and forming any air space within the latter, said inner structure including a fire box, air pipes disposed in the lire box and extending through opposite Walls thereof, the respective ends of the air pipes forming air inlets and outlets communicating With the air space of the furnace, and air boxes disposed in the fire box above and at right angles to the said air pipes, said air boxes extending through opposite Walls of the fire 4box one end of each air box being open at the under side for the inlet of air and the opposite end being open at the upper side for the outlet of air, the inlets and outlets of alternate air boxes being reversely disposed.

ROBERT LINCOLN POLLOCK 

